If water didn’t evaporate, we wouldn’t have clouds, and it would never rain! How does water evaporation cause rain? The water cycle is nature’s way of distributing water to things that need it. When liquid water evaporates into gaseous water vapor, it has completed one third of the all-important water cycle. Believe it or not, though, water evaporation and humidity serve a critical function of the natural world. Water vapor doesn’t seem like it’s useful for much of anything–other than making you uncomfortable. Liquid water is useful, plus, you know, essential for all life. It might sound like water evaporation is a bad thing. Hot places tend to be more humid than cool places because heat causes water to evaporate faster. The more water evaporates in a given area, the more water vapor rises into the air, and the higher the humidity of that area is. Humidity is the presence of water vapor in the atmosphere. When water evaporates, it rises and disperses into the surrounding air as the gaseous water vapor. We don’t see it happening, but under almost all normal atmospheric conditions, some volume of a mass of water evaporates and condenses in a constant cycle.
Humidity is the presence of water vapor in the atmosphere. Water rises and disperses into the surrounding air as the gaseous water vapor when water evaporates.